U.S. Pat. No. 5,626,161 (hereinafter called "prior art") to the same inventors of this application disclosed an automatic umbrella having triple folds for folding the umbrella ribs and the tubes of the central shaft. If it is intended to apply the mechanism of the prior art to be a quadruple-fold automatic umbrella which is folded to minimize its folding volume, it may incur a big problem for accommodating or winding the rope (56) within the umbrella structure when the rib assembly (2) and the telescopic central shaft (1) are retracted since there are just provided with two rollers including the upper roller (563) and the lower roller (564) for winding the rope (56) thereon.
Meanwhile, the control means (5) of the prior art for controlling the opening and closing of the umbrella is still complex and can be further simplified to minimize the elements in construction of the control means (5) in order to decrease the volume and weight of the complete set of the umbrella when the prior art is improved to be a quadruple-fold automatic umbrella.
The present inventor has found these drawbacks of the conventional automatic umbrella, and invented the present quadruple-fold automatic umbrella.